Unfortunately it's not that simple to add a feature like that. Word recognition and linguistics are way beyond a capabilities of this very simple and cheap plugin. There are services (google CSE or amazon) that provide such features, but it's very expensive, and require monthly payments.
Even if there was a solution to add to the plugin, it would probably require huge amounts of computational power, which is beyond a simple webhosting provider.

Best,Ernest MarcinkoIf you like my products, don't forget to rate them on codecanyon :)